'Undetectable bomb' threat: US urges increased security on international flights

Amid concerns of an Al-Qaeda effort to create an undetectable bomb, the US has ordered tighter security at some airports in Europe and the Middle East offering direct flights to the United States.

On Wednesday, Secretary of Homeland Security Jeh Johnson said he
directed the Transportation Security Administration to put more
security measures in place after sharing “recent and relevant”
information with foreign allies.

"Aviation security includes a number of measures, both seen
and unseen, informed by an evolving environment," Johnson
said in a statement.
"We will continue to adjust security measures to promote
aviation security without unnecessary disruptions to the
traveling public.”

American intelligence has picked up indications that bomb makers
from Al-Qaeda's Yemen affiliate, Al-Qaeda in the Arabian
Peninsula (AQAP), have traveled to Syria to link up with the
Al-Qaeda affiliate there, al-Nusra Front. The groups are working
to perfect an explosive device that could foil airport security,
a counterterrorism official told the Associated Press.

The move was not unexpected, as intelligence agencies, including
the Department of Homeland Security and the FBI, have been
debating
their options for months, and top-level officials met at the
White House last week to discuss the issue.

“[This threat] is different and more disturbing than past
aviation plots," one source told
ABC News earlier this week.

Radical Muslims traveling to war-torn Syria and Iraq pose a
threat to Western nations because they will be able to enter the
countries without visas on European passports.

"We've seen Europeans who are sympathetic to their cause
traveling into Syria and now may travel into Iraq, getting
battle-hardened. Then they come back," President Barack
Obama told NBC News in an interview broadcast Sunday.

Officials are concerned that bombs made with non-metallic
explosives could be surgically implanted in jihadists’ bodies.
Previous attempts by AQAP have involved suicide bombers with
explosives hidden in their underwear on commercial flights and
hidden in printer cartridges on cargo flights.

One of the places with heightened security will be British
airports. “The beefed up security will fuel fears of massive
queues at airports over the summer although the Department for
Transport said the extra measures - which have not been disclosed
- were not expected to cause ‘significant disruption’ and noted
that the official UK threat status remained unchanged,”
the Telegraph reported.

The measures may include closer scrutiny of personal electronics
and footwear, but government officials would not reveal any
specifics.

"We have taken the decision to step up some of our aviation
security measures. For obvious reasons we will not be commenting
in detail on those changes,” a Department for Transport
spokesman said. "The majority of passengers should not
experience significant disruption. There will be no change to the
threat level, which remains at substantial.”

"The safety and security of the public is our paramount
concern. The UK has some of the most robust aviation security
measures and we will continue to take all the steps necessary to
ensure that public safety is maintained."

Asked Monday by ABC News whether his European counterparts were
doing enough to address the threat emanating from Syria, FBI
Director James Comey said European authorities are "doing a
tremendous amount of work" but that it was "hard for
[him] to say" whether it's enough to prevent the threat from
materializing.